To determine whether the concentrations of air toxics
estimated in USEPA’s 1999 National-Scale Air
Toxics Assessment (NATA) could be a potential human
health problem in New Jersey, NJDEP compared the NATA
air concentrations to their chemical-specific health
benchmarks. To do this, we divided the modeled air
concentration by the health benchmark concentration
to get a number we call a risk ratio. If the risk ratio
for a specific chemical is less than one, the air concentration
should not pose a health risk. If it is greater than
one, it may be of concern. The risk ratio also shows
just how much higher or lower the estimated air concentration
is than the health benchmark. For more information,
see How We Estimate Risk
from Air Toxics.

New Jersey’s methods for estimating risk using
the 1999 NATA results are somewhat different from USEPA’s
methods. Therefore, risk results presented here
are different from the risk estimates found on the
USEPA NATA web site. For a discussion of these
differences, What's
Different about 1999 Nata?

Our
analysis of the state and county average air toxics
concentrations generated by NATA indicates that 22
of the pollutants were predicted to exceed their
health benchmarks in one or more counties in 1999.
21 of these are cancer-causing (carcinogenic) chemicals,
and one (acrolein) is not carcinogenic. Predicted
concentrations of these pollutants vary around the
state, depending on the type of sources that emit
them. This is summarized in the table below. For
more information click on point,
area, and mobile sources, and background
concentrations.

1999 NEW JERSEY CHEMICALS OF CONCERN

The following chemicals that USEPA included in the
1999 NATA modeling are of concern in New Jersey, because
their modeled average ambient concentrations are above
their health benchmarks in a county or across the entire
state.

1999 CHEMICALS OF CONCERN
IN NEW JERSEY

Pollutant

Number/Name
of Counties
Above Health Benchmarks

Primary
Emissions
Source

Acetaldehyde

21

Onroad, background

Acrolein

21

Mobile,
area

Arsenic
Compounds

4 (Atlantic, Camden,
Cape May, Gloucester)

Major, area

Benzene

21

Mobile

Bis(2-ethylhexyl)phthalate

21

Background

1,3-Butadiene

21

Onroad,
background

Cadmium
Compounds

1 (Warren)

Area

Carbon
Tetrachloride

21

Background

Chloroform

20

Area,
background

Chromium VI

14

Area

1,4-Dichlorobenzene

4 (Atlantic, Essex,
Hudson, Passaic)

Area

1,3-Dichloropropene

1 (Hudson)

Area

Diesel
Particulate Matter

21

Mobile

Ethylene
Dibromide

21

Background

Ethylene
Dichloride

11

Background

Ethylene Oxide

2 (Hudson, Warren)

Area

Formaldehyde

21

Mobile,
background

Methyl Chloride

21

Background

Naphthalene

14

Area

Nickel
Compounds

1 (Camden)

Area,
major

Perchloroethylene

10

Area,
background

1,1,2,2-Tetrachloroethane

21

Background

* For more information on which areas are impacted
by the chemicals of concern, see the chemical-specific
maps below.

To
see a statewide or county -specific table containing
the 1999 NATA-predicted air concentrations, health
benchmarks, risk ratios, and source category contributions
for each of the 22 air toxics of concern, click on
the state name or county names below.